I also base things on my understanding of how climate and weather work, from personal experience (residing and traveling), but also a lifetime of casual study (geography classes, news accounts, global warming blogs, histories, etc.).

Within reason -- given limitations in the AGE engine weather mechanism, and limits on time and effort; I am not a meteorologist or climatologist, and the weather mods are not a scientific study or PhD thesis! -- within reason, you can expect a fairly good weather model and representation of the real physical world.

In my weathers mods, there will be much less variability, fewer weather patterns, than in the unmodded, official games.

In my opinion, AGEOD has in some ways over-engineered its weather model (in other ways, under-engineered); the weather is too granular, with too many weather areas and terrain types. This is especially true of the earlier games (AACW, WIA, NCP). Simplifying is key.

But climate and weather are complicated and unpredictable, you might say. You might say; and I would respond:

* day-to-day weather differences; but game turns are not one day, rather 15 (or 30) days * freak snowstorms or cold snaps, especially to the south; in real life, they do happen, but rarely, and usually dissipate quickly * inverted continental temperature patterns (warm to the north, cold to the south; or warm to the west, cold to the east); but in real life, these are atypical, are not at all usual * the "Little Ice Age" -- roughly the 16th through the 19th Centuries -- and the generally somewhat colder weather toward the end of that age compared to our current weather; but the differences are "somewhat" (in real life, real history), not drastic (as sometimes in the official games)

We are looking to average normal weather over time (15 days, or 30 days) and space (the game map). Variety may be the spice of life, and for some people make for more interesting game play; but my preference is for realism, and plausibility. These are serious historical simulations, not anything-goes fantasy games. My opinion.

So game weather will be blander and more boring than what you are used to.

In my weathers mods, I strive to follow these general principles:

* colder to the north, warmer to the south * colder in the uplands (hills and mountains, and depending on the game, also wilderness, taiga, etc.); warmer in the lowlands and toward the coasts * consistency east to west (not north to south) * broad banding, averaging out weather over the 15-day (or 30-day, in the case of WIA) game turns * no "crazy quilts" or "peek-a-boo" (now you see it, now you don't)) weather patterns, or as little as possible

In order to achieve the desired effects, I have to

* in all games, re-assign some regions from one weather area to another * in some games, reduce the number of weather areas * in all games, constrain each region to just one or two "adjacent" weather possibilities in any given month

Region re-assignments:

In the official game data files, regions are sometimes mistakenly assigned from one adjoining weather area to another, leading to "orphans", "holes", and "fingers". At other times, there are outright goofs (for example, in RUS assigning the southern Steppe region $Alexandrovsk to the northern Subarctic weather area). These must be corrected.

Reducing the number of weather areas:

Here are some typical weather areas (in this case, from the WIA/GameData/Areas.ini file):

and reassigning the member regions to another weather area (in the example, to Eastern_Great_Lakes).

(The consolidated regions are therefore sometimes misnomers. In the above example, I would like to rename Eastern_Great_Lakes as simply "Great_Lakes". But that would necessitate changing too many game data files. To ease mod installation, I try to keep things simple, and just live with some of the misnomers. But this is behind-the-scenes stuff that shouldn't matter to you, the gamer.)

In the most extreme case -- WIA -- I have reduced the number of active weather areas from the default 19 down to the mod 7. In other cases -- ROP & RUS -- the number of active weather areas is unchanged (but still with region re-assignments among areas).

More tightly constraining weather possibilities:

Here are some typical weather specifications (in this case, from the ROP/GameData/Weathers/WeatherPatterns_Interior_Uplands.ini file):

As you can see, each terrain type is limited to just one or two "adjacent" weather possibilities in any given month. For example: 100% chance Snow; or 50% chance Mud, 50% chance Snow. To allow three or more possible weathers for a given region and month is to invite inverted weather/temperature patterns, "checker board" patterns, or worse.

Contrast the above with some typical standard defaults (in this case, from the official ACW/GameData/Weathers/WeatherPatterns_Weather_Upland_South.ini file):

I use a Perl script (program), mkweathers.pl, to generate the month-to-month weather parameters (chances) for each weather area and terrain type.

You don't need to run this script, or to understand its operation; that's my job. Just know that the script helps to ensure consistent treatment across all climate types, across all terrain types, across all games. The various Weathers *.ini files are a great mass of data. mkweathers.pl helps to make sense of it all, to manage all the complexity, and to reduce outliers, typos, and other mistakes (such as the combined weather chances exceeding 100% for any given month and terrain type).

How do my modded weather parameters compare to the AGEOD official defaults? To answer that question, I use another Perl script, ageweathers.pl, to compute concise, concise, easy-to-see cross references of one game's weather specifications to another's. In my weathers mods, you can expect many changes, but I try not to stray unnecessarily far from the official AGEOD standards and defaults.

For the latest version of mkweathers.pl & ageweathers.pl, (also the latest version of the Weathers Mods, other scripts, and possibly other useful stuff), visit

After all the region corrections, re-assignments, consolidations; after specifying the weather parameters (chances); after performing some rigorous, comprehensive QA (using AGElint, and by other means); after all of that, I tested, tested, tested. Based on my tests, I am fairly well satisfied with the AACW, ROP, RUS & WIA Weathers Mods results. Not perfect. But good enough. Certainly better than the standard defaults.

There is much more I could say, but let's keep this short (ha!). For more, much more discussion, please see any of

* I am not a climatologist. (I only play one on TV.) * My criticisms of AGEOD games weather modeling may be out of date. The official game weathers may have changed recently, or since I have written this. * The AGE weather model is imperfect (what isn't?), and limits what we can achieve. There are some maddening quirks and gotchas in the AGE weathers system, also in the game data files. We try to do the best we can, given all the constraints, and the mod objectives. * I am diligent, and careful, and to the best of my ability I QA my work and strive to give you the best product reasonably possible. I make my share of mistakes, but except for honest differences of opinion, I correct my goofs!

So, that in a nutshell (well, a bagful of nutshells) summarizes my Weathers Mods.

Following are some examples of why I think the default WIA weathers are odd, questionable, and even repugnant (to the point where, at its extreme, I no longer want to play the game).

All the examples are from just a handful of test games. I did not have to run through many different test games to cherry pick the worst examples. These are commonplace weather patterns, typical of each and every WIA game.

Here is a typical weather pattern. April 1763, warmer weather to the north in Canada

but colder weather to the south around Texas (and Oklahoma and Arkansas)

Does this seem reasonable to you?

Before you answer that question, consider (sharing my observations, and expressing my opinions):

In WIA, game turns are one month. Weather should represent average weather patterns across 30 days, not short-term weather, or passing weather fronts.

In WIA, weather anomalies are the rule, not the exception.

People might cite freak snowstorms or cold snaps in the Deep South, or the rare occasions of inverted continental temperature patterns (warm to the north, cold to the south). But in real life, these are "freak" and "rare". In WIA the game, these are commonplace.

People might cite the "Little Ice Age" (roughly the 16th through the 19th Centuries) and the generally somewhat colder weather toward the end of that age compared to our current weather. But the differences are "somewhat" (in real life, real history), not extreme (as in the game).

May 1763, again warmer weather to the north in Canada

but colder weather to the south around Arkansas

Again, does this seem reasonable to you?

Note that, in both examples, we are comparing mountains to mountains ("apples to apples"), so elevation doesn't factor into it.

June 1763, again generally warmer weather to the north in New England

but, um, snow in the Berkshires in June, for an entire month? Surrounded all around (including mountains and wilderness) by rain/fair weather regions?

Does this seem reasonable to you?

October 1764, snow down south around Oklahoma but no snow anywhere else on the game map

Does this seem reasonable to you?

In this game, a very pronounced Ice Age in the Southern Plains! You tend to see snow around Texas, Oklahoma and Arkansas very often. And late into spring even.

Isolated pockets of anomalous weather:

Do these seem reasonable to you?

Again, this is due to the way WIA the Game computes the weather (weather determined randomly region/terrain by region/terrain, with only accidental correlation across regions/terrains).

April 1763, more oddities:

Crazy quilt!

Note that many of the snowy areas down south are lowlands, not upper elevations (mountains).

(Note also that I didn't have to go very far to find this one odd example. This is the weather pattern of another test game's very first turn.)

April 1763, from another test game, more crazy quilt patterns:

Does this seem reasonable to you?

I drew the above examples firstly from just a single test game (of the Pontiac's War scenario), then two consecutive reloads. No need to wait very long to see weather strangeness (IMHO). You can see it almost every turn, almost everywhere you look.

Corresponding to the broad climate types in the eastern half of the United States displayed here:

And the eastern half of Canada displayed here:

Yes, the consolidated Eastern_Great_Lakes uber weather area now encompasses the discarded (emptied) Western_Great_Lakes weather area. So "Eastern_Great_Lakes" is somewhat of a misnomer. What I'd really like to do is to define, in Areas.ini, an entirely new weather area, simply Great_Lakes (and also Upper_Canada, Middle_North, Upper_South, etc.). But that would necessitate edits to WIA/Aliases/MetaAreas_Aliases.ini & WIA/GameData/AreasExtInfos.ini. Also, it would complicate merges with updated official WIA/GameData/Areas.ini. I shouldn't rewrite the game weather system more than necessary, or overly complicate the mod install process. So, I live with the weather area misnomers -- not pretty from a programmer viewpoint, but this behind-the-scenes stuff should be effectively transparent to the users.

In my weather uber areas, and so as to avoid unnecessary confusion, I am naming them in conformity with my AACW Weathers Mod. (For example, there is a North_Plains weather area in AACW, so we go with the similarly named Northern_Plains weather area in WIA.)

In fixing the WIA weathers, the first steps are to

Reduce the number of weather areas, and conform them to actual, real-world climate. (There are way too many weather areas in official WIA. And many of the 20 don't conform well at all to realistic climate bands (e.g., run north to south, not east to west).

Reassign regions as necessary (empty and consolidate).

Correct region misassignments (goofs in the original, official Areas.ini).

In my revised Areas.ini file, I am undertaking those first several steps.

I invite you to download the 20120907 release of my weathers mod, which features the v0.9 WIA Weathers Mod (also updates to the AACW, ROP & RUS Weathers Mods over the past week). Get the entire package (which includes unfinished, works-in-progress weathers mods for several other AGEOD games) here:

(Note: You might wait a bit, because I anticipate issuing a thoroughly tested, at or near v1.0, weathers mod package -- encompassing the AGEOD games AACW, ROP, RUS & WIA -- by the second week of September 2012. So be sure to check back later.)

Based on my tests, I am getting close to satisfied with the AACW, ROP, RUS & WIA Weathers Mods results, satisfied enough that I really do foresee releasing 1.0 versions of these mods within a week or less.

The WIA Weathers Mod (so too the others) should be compatible with any ongoing game-in-progress. (If you apply the mod, then reload a saved game, the mod won't take effect until the next turn in your game.) Feel free to apply and test!

Snow in most of Canada, but not in Forest regions along coastal Lake Ontario north, or along the Atlantic coast. Snow in in the "snow belt" Wilderness regions along southern and eastern Lake Ontario.

No more "holes", "orphans", "fingers", or "crazy quilts" (except where climate science and the AGEOD-specified region terrain types mandate them). A plausible treatment of rain/mud patterns across the map, and in all seasons, too. A model of game weathers more consistent with climatological facts (as I interpret them).

With my WIA Weathers Mod, what you see is what you'll get. Subject to possible further tweaks. But all in all, I'm really happy with these results. I hope you'll agree.

I have released v1.2 of my Weathers Mod for AGEOD's Wars in America (BoA2).

v1.2 delays the onset of winter by a month. November weather is now more like April weather, not like March. May rain/mud has been reduced. (And pertinent to RUS, winter has been scaled back in desertic steppe regions.)

The overall impact is to lengthen the effective campaigning season by up to a month, at both beginning and end.

Please download the 20121129 release of the WIA weathers mod (also weathers mods for several other AGEOD games) here:

In v1.2 of the Weathers Mod, the Areas.txt file is unchanged. Only the Weathers/*.ini files have changed. Updating from the previous version is as easy as copying the new Weathers/*.ini files in place.